This invention relates to electrical connectors and, more particularly, to a coaxial connector having a central spring-loaded pin electrode encircled by a circumferential shoulder electrode in which spring-loaded contact pins may be mounted.
Coaxial cables are widely used in the transmission of electric signals. Such cables have an inner conductor disposed along the axis of the cable, and an outer conductor disposed circumferentially about the inner conductor in the manner of a shield or sleeve. The inner and other conductors are spaced apart by a coaxial layer of insulating material of suitable dielectric characteristics for establishing a desired impedance to the cable. Such cables are manufactured in a large variety of sizes including both large and smaller diameters. Connectors at the termini of the cables maintain the coaxial configuration in the arrangement of the connector components. The connectors are usually structured as male and female counterparts and include a locking device, such as a spatial groove and tooth, for secure engagement of connectors to each other.
There is particular interest in the use of coaxial cables in the testing of semiconductor microcircuits. In a complex circuit, there may be many terminals which are to be connected to testing apparatus and, accordingly, many cables are to be employed in the connection of the semiconductor microcircuit to the testing apparatus. In the case of the testing of microcircuits formed as chips with electrodes in the form of pads, the sizes of the pads and their spacing are too small to connect with even the smallest sizes of coaxial cable. Accordingly, devices have been constructed which interface between a set of pads and coaxial cable connectors.
A problem attendant the use of such interfacing devices is the compromise between bandwidth and the physical size of the device necessary to accommodate standard coaxial connectors. Thus, the physical size of presently available coaxial connectors places restraints on the construction of the interfacing device. This may be readily appreciated because the interfacing device esentially transforms the spatial array of the microcircuit pads to the spatial array of the coaxial connectors.
Even if the pads of the microcircuit were enlarged, no direct connection could be made between the connector and the pad because presently available connectors are not configured for mating with a flat surface.